在区块链上/下存储图像？ 哪个更好？

Question

I'm using hyperledger fabric and need to store images but don't know what is the best way to store is it on or off the blockchain? both have their pros and cons. should sacrifice the security of the images or the performance of the network?

Answer 1

Blockchains are not suitable for storing big size data. There are drawbacks such as the replication rate and limitations such as the block size.

So I recommend using an off-chain storage system. A common approach is using IPFS, a P2P distributed storage system. IPFS provides availability, higher performance and integrity (as files are referenced by their hash). The IPFS hash can be saved suitably on the blockchain. IPFS is available as a public P2P network, but you can also deploy your own private IPFS network.

If using IPFS, I also recommend using IPFS-Cluster over IPFS, to manage persistence and replication.

• https://ipfs.io/
• https://cluster.ipfs.io/

If you need encryption (maybe you don't), you should implement it outside IPFS (in your clients). How do you implement it, is up to you and your use case. As @GraphicalDot suggests in its comment, you can encrypt your file via AES and store the key in the blockchain (encrypted in turn via ECIES or ECDH) if you need user-level encryption (although if have its drawbacks if your user enrolls new keys). Anyway, Fabric itself only provides privacy at organization level (not at user level).

Answer 2

I think the answer also comes down to the business case of why you want to store images on chain. If you are trying to establish provenance, you can do that with metadata stored on chain and the images off chain, etc. If you want to make sure the images are stored for immutability, then maybe, but if you want to be able to delete them or modify them down the road, then maybe not.